What are Microservices and Why Do You Need Them?

Your company is running a major application that’s central to your business and it’s time for an update. It’s a small change — just one piece of the app needs a refresh — but everyone is dreading it. Why? The software was built as one big application, changing one piece of the code may mean that other code will break. It’s like playing dominos — each fix means something else could break. It should be a simple update but everyone involved knows that it’s probably going to be a project.

There is a way your organization can avoid playing games of domino with your applications in the future — by using microservices, a software architecture style made popular in the last four years by Netflix. That popularity is growing. According to IDC, 90 percent of all new apps will feature microservices by 2022.

But what are microservices and why do you need them when you’re designing your custom app? Read on for answers.

What is microservice architecture?

Microservices — or microservice architecture, as it’s also called — isn’t a thing. Rather, it is a principle of software architecture used in software development. Under this concept, developers break up applications into their component parts.

When software is built as a monolith, it’s built all at once, and in one large piece. But when software is developed using microservice architecture, it's developed as a set of tiny, standalone applications that can be constantly changed and upgraded without blowing up the entire application.

Because those microservices are, in themselves, self-contained applications, when you update one, or swap an old one for a new one, the rest of your software is unaffected. If, on the other hand, you’re trying to change one part of an application that was developed as a monolith, that one line of code and any changes to it, may have far-reaching, unforeseen effects.

The difference between monolithic architecture and microservices is the difference between knitting an afghan out of one long piece of yarn and making a quilt out of different pieces of fabric. It’s hard to change part of the afghan, because it’s been made as a monolith. If you cut it to add rows in the middle, the afghan will unravel. But if you need to change part of a quilt, which is made of different pieces of self-contained fabric, all you need to do is swap in a new square of fabric.

How do microservices work?

A microservice is written very specifically, usually to perform one service; “get customer data,” for example. If that microservice breaks, it can be removed and replaced with another module that works, with minimal disruption to the application as a whole.

Part of the reason microservices work so well for Netflix for example, is that the streaming service is constantly changing its offerings. Because its services change between five and 10 times a month, Netflix needs to be able to quickly and easily change its app without its users noticing.

In fact, an end user shouldn’t be able to tell if they’re using an application that was designed using the microservice approach. It ought to perform in exactly the same way for a user as an app designed taking the monolithic approach would. The differences in the architecture just make changes easier and less disruptive.

Microservices also works well for companies running DevOps. DevOps prioritizes frequent releases of apps and services, so microservices — which let developers update applications quickly and manageably — is a natural fit for DevOps teams.

While an app designed using a monolithic approach has to be updated all at once — with 500 service calls in one package, for example — an update done under microservices might include 30 service calls.

Microservices: Where to start?

Still confused about microservices or interested in migrating to a microservice architecture approach in your custom app development? If so, there are a couple of questions you need to answer before you begin.

·     Is your organization using (or interested in) DevOps?

·     Do you need to update your application frequently?

If the answer to both of those questions is yes, it’s time to consider microservices.